Determining the location or motion of a wireless emitter may be important in many applications; for example, military operations may need to determine the location of an enemy unit via tracking the location of a wireless emitter used by that unit. These wireless emitters may be referred to as “hostile” or “non-cooperative” emitters, as they do not intentionally broadcast geolocation information, and may be actively attempting to avoid detection. Non-cooperative emitters may also be narrow-band radio-frequency emitters, further complicating the problem of finding non-cooperative emitters. Methods and apparatuses that can locate such non-cooperative emitters may be significant in a wide range of applications.